Moving Wearable Magnetoencephalography Measurement Study Based on Optically-pumped Magnetometer

Abstract

Magnetoencephalography is a non-invasive technology for brain function imaging, which is of enormous value to brain science research and clinical application due to its ultra-high temporal and spatial trace resolution. In this paper, we introduce a self-built and atomic magnetometer based wearable magnetoencephalography system. By designing bi-planar coils system and combining with reference sensor array, the residual magnetic field in the subject's head movement area is controlled to be within ±1 nT, which ensures the sensors are maintained within their dynamic range during the moving measurement. At the same time, a virtual gradiometer-based noise reduction method is proposed to suppress the common-mode magnetic-field noise. Finally, the alpha rhythm and auditory evoked magnetic field signals with high signal-to-noise ratio are successfully detected under the subject's natural head movement and the effectiveness of the system is confirmed. This study could provide more possibilities for the application and promotion of moving wearable magnetoencephalography.

Keywords

• wearable magnetoencephalography
• optically-pumped magnetometer
• moving measurement
• field nulling
• noise reduction